What is Magnesium?
In the most general sense, magnesium can be thought of as an energy-enhancing, healthy stress response-supporting nutrient, beneficial for both mind and body.*
Magnesium is a factor in over 325 enzymatic reactions throughout the body, and is an integral player in the production and utilization of cellular energy.* Without sufficient magnesium, cells can’t produce the energy they need to adapt, and all manner of stress reactions are then amplified.
Magnesium supplementation has often been suggested to ease the mood-related symptoms of occasional stress, including irritability,* fatigue,* nervousness,* or occasional sleeplessness.* the healthy stress-response supporting effects of magnesium can also impart remarkable benefits upon physical performance as well.*Many people find magnesium helpful for supporting flexibility,* reducing muscle soreness,* and for helping reduce muscle spasms and cramping.*
In helping to counter the stress of athletic training, magnesium has also been suggested to support healthy balance in levels of the stress hormone, cortisol, and (in males) to promote the production of recovery-enhancing testosterone in response to exercise.*
Ultimately, every biological function depends, either directly or indirectly, upon the presence of sufficient magnesium—a fact which makes the widespread incidence of magnesium deficiency in industrialized nations all the more alarming.
How prevalent is magnesium deficiency?
Research suggests that many of us (even if we try to consume a healthy diet) are falling far short of meeting even our bare minimum magnesium requirements. Our current magnesium intake falls far below historical levels as well. Researchers have estimated that before the year 1900, the average daily magnesium intake in the United States was around 450 mg. But recently, the United States Department of Agriculture’s National Health and Nutrition Examination Survey (NHANES) from the years 1999 and 2000 found that the average daily intake of magnesium is currently nearly a third less than these levels. The survey found that almost 68% of modern Americans may not be consuming the recommended amount of magnesium each day, and nineteen percent of those surveyed failed to consume even half of the recommended daily intake (RDI) for magnesium.
And, because magnesium is depleted by intense exercise, athletes and bodybuilders may be at particular risk of sub-optimal magnesium intake. Athletes lacking magnesium may notice excessive muscle soreness and cramping, and, because magnesium is involved in keeping cortisol at bay and supporting testosterone, sub-optimal magnesium intake may short-circuit muscle growth and recovery.*
Diabetes linked to magnesium deficiency
Magnesium plays an essential part in the regulation of many cell and metabolic processes. This probably explains the accumulating evidence that magnesium improves blood sugar control. Judging by the results of a new study, having low magnesium blood levels worsens diabetes complications.
The results show that magnesium intake was inadequate in 82 percent of the diabetics studied, with the lowest levels found in those with kidney complications. Further, about two-thirds (63 percent) of the subjects had low blood levels of magnesium.
Top magnesium sources
According to USDA data, the top food sources of magnesium include these, in descending order of magnesium content:
- Cocoa powder – 456mg per 3 oz (27mg per Tbsp)
- King salmon – 122mg per 3 oz, cooked
- Halibut – 90-107mg per 3 oz, cooked
- Sablefish – 71mg per 3 oz, cooked
- Almonds or cashews – 225-240mg per 3 oz (75-80mg per oz)
Other major food sources include:
- Leafy green vegetables
What about supplements?
Conventional wisdom calls for taking about one part magnesium to two parts calcium.
But other researchers argue, persuasively, that a one-to-one ratio is healthier, given the overload of calcium in most Americans’ diets, and the lack of magnesium. Studies have shown that prehistoric diets seem to have provided the minerals in a one-to-one ratio, suggesting that this ratio relates to how humans have evolved.
What are the best forms of supplemental magnesium?
Recent research conducted by Albion® Nutrition—the world leader in the science of mineral nutrition—examined the absorption of several different types of magnesium. Their study suggests that buffered magnesium glycinate chelate and dimagnesium malate (the two types of magnesium in Integrated Supplements Bio-Available Magnesium) were better-absorbed than both unbuffered magnesium glycinate and magnesium oxide. Average serum levels of magnesium after the ingestion of each compound is shown in the chart below.
Finally, magnesium aids calcium absorption into bones, but the opposite is not true, with excess calcium impeding magnesium uptake.
Last year, a USDA researcher published an evidence review, in which he made several key points (Nielsen FH 2010):
- About 60 percent of American adults do not consume sufficient magnesium.
- Low magnesium levels are associated with many disease conditions characterized by chronic inflammation, including obesity.
- Magnesium deficiency may contribute significantly to development chronic diseases such as atherosclerosis, hypertension, osteoporosis, diabetes mellitus, and cancer.
Before we take a look at a recent Brazilian study that strengthens the link between diabetes and magnesium, let’s review the existing evidence.
Low blood magnesium levels linked to diabetes risk and complications
Epidemiological studies suggest that adequate magnesium intake reduces the risk of developing diabetes significantly.
But the links between low magnesium blood levels and greater risk of the disease and worse symptoms is even greater …possibly indicating that some diabetics have difficulty using magnesium they consume.
The body’s capacity to produce insulin relies in part on magnesium, which is needed for the activation of insulin receptors and for stimulation of body chemicals involved in insulin “signaling”.
And the chronically high blood sugar levels (hyperglycemia) that characterize diabetes lead to excessive loss of magnesium in the urine while increasing the risk of kidney damage and other complications associated with diabetes.
New study puts more importance on Magnesium
The new research, conducted in Brazil, examined magnesium intake and blood levels in 51 patients with type 2 diabetes. And the results tied the diabetics’ blood sugar (glucose) levels to their blood magnesium levels.
Specifically, those with higher blood magnesium levels had lower fasting and after-meal blood glucose levels.
In addition, higher urine levels of magnesium were linked to higher fasting glucose levels.
The authors noted that because magnesium is essential to all reactions that use and supply energy, it is not very surprising that low blood levels of the mineral are implicated in metabolic dysfunctions like diabetes.
They concluded that the impaired kidney function associated with diabetes may lead to high levels of magnesium in the urine, which, together with low magnesium intake, can cause a rise in blood sugar.
- Sales CH, Pedrosa LF, Lima JG, Lemos TM, Colli C. Influence of magnesium status and magnesium intake on the blood glucose control in patients with type 2 diabetes. Clin Nutr. 2011 Jan 31. [Epub ahead of print]
- de Lordes Lima M, Cruz T, Pousada JC, Rodrigues LE, Barbosa K, Canguçu V. The effect of magnesium supplementation in increasing doses on the control of type 2 diabetes. Diabetes Care. 1998 May;21(5):682-6.
- Kao WH, Folsom AR, Nieto FJ, Mo JP, Watson RL, Brancati FL. Serum and dietary magnesium and the risk for type 2 diabetes mellitus: the Atherosclerosis Risk in Communities Study. Arch Intern Med. 1999 Oct 11;159(18):2151-9.
- Wang JL, Shaw NS, Yeh HY, Kao MD. Magnesium status and association with diabetes in the Taiwanese elderly. Asia Pac J Clin Nutr. 2005;14(3):263-9.
- Nielsen FH. Magnesium, inflammation, and obesity in chronic disease. Nutr Rev. 2010 Jun;68(6):333-40. Review.
- Barbagallo M, Dominguez LJ. Magnesium and aging. Curr Pharm Des. 2010;16(7):832-9. Review.